In order to anchor pins of this type in the connector body, EP-A-0 647 986 discloses providing them with at least two pairs of lateral retaining wings situated opposite one another on the contact pin. The contact pins are press-fitted from the connection side into receiving chambers of a male strip connector or the like. In the process, top faces which diverge in the shape of a wedge on the retaining wings displace part of the material surrounding the chamber. After the passage of the retaining wings, some of the material returns to its initial position. In the process, it comes to lie on retaining faces at the rear side of the wings and in this way produces resistance against the pin being forced out counter to the press-fitting direction. This resistance can be improved only to a limited extent by the use of a stronger material, because the stronger the material is, the smaller is the portion which returns to the initial position and forms the support for the retaining faces. For this reason, pins can easily be forced out when the male strip connector is plugged together with a complementary female strip connector, which may lead to the failure of assemblies or equipment. The overall loadability could be improved if the wings could be enlarged. However, this is not practical for a number of reasons.
The larger the wings are, the higher, too, are the stresses which occur when the pins are press-fitted into the connector body. This can easily lead to the body buckling or even tearing, particularly in the case of multi-pole miniature connectors, which contain a large number of closely adjacent contact pins. Moreover, if the wings are produced by embossing the pin material, their size is limited by the material cross-section available for deformation.
The loadability of the known pin in the plugging direction frequently does not satisfy the relevant requirements.